(213e) Metabolic Modeling of Pseudomonas putida KT2440 tounderstand and improve the breakdown of plastic waste

Polyethylene terephthalate (PET), the polymer used to manufacture plastic beverage bottles, is the world’s highest production-volume synthetic plastic. While synthetic polymers are typically resistant to biodegradation, organisms have been discovered that can decompose PET into soluble but toxic monomers, ethylene glycol (EG) and terephthalic acid (TPA). Pseudomonas putida is a soil bacterium known for its receptiveness to genetic engineering and ability to metabolize a wide assortment of organic compounds and pollutants. We seek to understand the pathways by which P. putida can metabolize EG and/or TPA and whether its growth on these compounds could be improved by genetic modification. Our analyses are based on whole-genome metabolic models of P. putida accessed with the web platform KBase and locally implemented in a Python programming environment, COBRApy. These models are used to generate flux balance analysis (FBA) outputs that allow us to quantitatively predict the organism’s growth in different media. FBA results indicate that P. putida KT2440, described by the model iJN1463, is capable of biomass formation on EG. We are currently investigating growth on TPA. Our research has uncovered metabolic “bottlenecks” that, if alleviated by genetic engineering, could improve the ability of P. putida to metabolize these carbon sources.